Hey, I just thought of something.
Is your vacuum advance working?
It is a 95, so its a 3.9. When the advance gets stuck, the power really suffers.
You can confirm this by checking your timing, at idle.
Disconnect the hose that goes from your throttle plate to the distributor.
Dont worry about plugging the nipple on the plenuim. It's cut off by the throttle plate. That nipple only gets vacuum when the throttle is opened.
Apply vaccum to the hose, and the timing should move....I use a vacuum pump, and wtach the timing with a light while i pump it.
I have the spec at work, but really, ifyou see some change, it's likely working. Usually, when they go bad, vacuum has no change.